In Patent Document 1 and Patent Document 2, catalysts for producing an α,β-unsaturated carboxylic acid by carrying out oxidation of an olefin or an α,β-unsaturated aldehyde with molecular oxygen in a liquid phase (expressed as “liquid-phase oxidation”) and methods for producing the same are disclosed.
Patent Document 1: Japanese Patent Application Laid-Open No. 2004-141,828
Patent Document 2: International Publication No. WO 02/083,299